SIVATHEEIUM GIGANTEUM. 



257 



Among a quantity of bones collected in the neighbotu'liood 

 of the spot in which the skull was found there is a fragment 

 of the lower jaw of a very large ruminant, which we have 

 no doubt belonged to the Sivatherium ; and it is even not 

 improbable that it came from the same individual with the 

 head described. It consists of the hind portion of the right 

 jaw, broken off at the anterior third of the last molar. The 

 coronoid apophysis, the condyle, with the corresponding part 

 of the ramus, and a portion of the angle, are also removed. 

 The two posterior thirds only of the last molar remain ; 

 the grinding surface is partly mutilated, but is sufficiently 

 distinct to show the crescentic plates of enamel and proves 

 that the tooth belonged to a ruminant. The outline of the 

 jaw in vertical section is a compressed ellipse, and the 

 outer siu-face is more convex than the inner. The bone thins 

 off, on the inner side towards the angle of the jaw, into a 

 large and well-marked muscidar hollow; and rimning up 

 from the latter, upon the ramus towards the foramen of the 

 artery, there is a well defined furrow, as in the Kuminantia. 

 The surface of the tooth is covered with very small rugo- 

 sities and striae, as in the upper molars of the head. It had 

 been composed of three semi-cylinders, as is normal in the 

 family, and the advanced state of its wearing proves the ani- 

 mal from which it proceeded to have been more than adult. 



The form and relative proportions of the jaw agree very 

 closely with those of the corresponding parts of a Buffalo. 

 The dimensions compared with those of the Buffalo and Camel 

 are thus : — 



No known ruminant, fossil or existing, has a jaw of such 

 a large size ; the average dimensions above given being more 

 than double those of a Buffalo, which measured in length of 

 head 19'2 inches (•489 metres), and exceeding those of the 

 corresponding parts of the Rhinoceros. We have, therefore, 

 no hesitation in referring the fragment to the Sivatherium 

 giganteum. (See Plate XXI. fig. 1.) 



The above comprises all that we know regarding the 

 osteology of the head from an actual examination of the 



VOL. I. s 



